In conventional elevator group management systems, a linear sum of an increment value of waiting time and an increment value of energy consumption is computed as a cost function for a newly generated hall call (call of an elevator in an elevator hall), and a car with the smallest cost function is decided as an assigned car to the newly generated hall call. The method of deciding an assigned car as described above is disclosed in, for example, Patent Document 1 as the method of assigning hall calls.
Further, Patent Document 2 discloses the method of evaluating the power consumption required for travel to destination floors corresponding to a currently generated hall call and a hall call, to thereby assign a car in response to a new hall call.
Further, Patent Document 3 discloses the assignment method of achieving, by the means for obtaining an estimated load evaluation value, easier assignment as the value of a car load evaluation value is closer to a balanced load.
Further, Patent Document 4 discloses the assignment method of deciding start intervals, assigned cars and the like according to a traffic flow for reducing power consumption evaluated from the car load. For example, car start intervals are controlled so as to obtain a balanced load at up peak. In addition, at down peak, hall calls are centered on one elevator or put on standby such that a car load upon arrival at a lobby floor becomes almost full and a motor load is reduced.
On the other hand, Patent Document 5 discloses the method of performing an assignment by evaluating the power consumption as a result of responses to all calls (during registration).
In addition, Patent Document 6 discloses the assignment method in which power consumption is taken into account in tuning a group management parameter with respect to a traffic flow.